NIH has called for research to decrease the prevalence of smoking and obesity. The proposed study addresses both challenges in the context of smoking cessation quit lines. New data indicates that over two thirds of quitline callers are overweight or obese, a distribution that is similar to the general population. Because smoking and obesity are the leading modifiable risk factors for increased mortality and morbidity, failure to address them drives major costs associated with the provision of health care for chronic disease. Although smoking cessation is advised, quitting is associated with weight gain and an increase in metabolic disorder. Efficacy trials reveal that combined cessation and weight control treatments are feasible and can prevent weight gain without harming quit rates. However, those trials were based on intensive, face to face group treatments that are unlikely to be broadly implemented across the population. The aim of this study is to test the effectiveness and cost effectiveness of combined cessation and weight management treatment in a real world sample of smokers (n=2550) seeking cessation services via quitlines operated by the nation's leading vendor of telephonic-based smoking cessation services, Free & Clear, Inc. (F&C). This study will also test whether smokers are able to address both cessation and weight control simultaneously, or if sequentially addressing smoking first, then weight control is optimal. Persons will be eligible for the study if they use the F&C Quit for Life program and agree to be randomized to one of three groups (standard quitline care or standard care plus weight control delivered concurrent with or sequential to standard care). This study is unique in that it would be the first to test the effectiveness of combined cessation and weight management treatment in a quit line context. It also tests whether a simultaneous or a sequential approach is helpful or harmful to quitting, as compared with cessation treatment alone. The trial is timely and important and likely to have public health significance and to be of interest to providers, policy makers, researchers and consumers. PUBLIC HEALTH RELEVANCE: The obesity epidemic and the health risks associated with weight gain which commonly accompanies cessation points to the urgent need for widely available, evidence based cessation interventions that prevent weight gain. This randomized trial will examine the effectiveness and cost effectiveness of weight control concurrent with or sequential to a standard smoking cessation quit line. Knowledge learned from this innovative effectiveness trial could have a significant impact on preventing cessation related weight gain.